Speakers are widely applied in mobile devices, such as mobile phones, tablet computers, laptop computers, portable game players, portable multimedia devices, or the like, for converting electrical signals into audible sounds. A related speaker includes a vibration system, a magnetic system, and a holder for holding the vibration system and the magnetic system. The vibrating system includes a membrane and a coil connected to the membrane for driving the membrane to vibrate and produce sound.
Generally, when the speaker in applied in the mobile device, the coil of the speaker needs to drive the membrane to vibrate with sufficient vibration amplitude, so that the speaker can obtain have a better low frequency response; in other words, the speaker is required to have a long stroke. However, a miniaturization trend of the mobile device may restrict an inner space of the speaker and thus the vibration amplitude of the membrane is limited. Accordingly, the low frequency response of the speaker may be impacted.
Therefore, it is desired to provide a new speaker which can overcome the aforesaid problems.